Comparison of histomorphometric and radiographic effects of growth guidance with tension-band devices (eight-Plate and FlexTack) in a pig model

Andrea Laufer; Julia Sattelberger; Hauke Hillebrand; Georg Gosheger; Adrien Frommer; Sebastian Appelbaum; Ahmed Abdul-Hussein Abood; Martin Gottliebsen; Ole Rahbek; Bjarne Moller- Madsen; Robert Roedl; Bjoern Vogt

doi:10.1080/17453674.2021.1873603

Authors

Andrea Laufer Department of Pediatric Orthopaedics, Deformity Reconstruction and Foot Surgery, University Hospital Muenster, Germany
Julia Sattelberger Department of Pediatric Orthopaedics, Deformity Reconstruction and Foot Surgery, University Hospital Muenster, Germany
Hauke Hillebrand Department of Pediatric Orthopaedics, Deformity Reconstruction and Foot Surgery, University Hospital Muenster, Germany
Georg Gosheger General Orthopaedics and Tumour Orthopaedics, University Hospital of Muenster, Germany
Adrien Frommer Department of Pediatric Orthopaedics, Deformity Reconstruction and Foot Surgery, University Hospital Muenster, Germany
Sebastian Appelbaum Department of Research Methodology and Statistics in Psychology, University of Witten/Herdecke, Germany
Ahmed Abdul-Hussein Abood Danish Paediatric Orthopaedic Research, University Hospital Aarhus, Denmark
Martin Gottliebsen Danish Paediatric Orthopaedic Research, University Hospital Aarhus, Denmark
Ole Rahbek Danish Paediatric Orthopaedic Research, University Hospital Aarhus, Denmark
Bjarne Moller- Madsen Danish Paediatric Orthopaedic Research, University Hospital Aarhus, Denmark
Robert Roedl Department of Pediatric Orthopaedics, Deformity Reconstruction and Foot Surgery, University Hospital Muenster, Germany
Bjoern Vogt Department of Pediatric Orthopaedics, Deformity Reconstruction and Foot Surgery, University Hospital Muenster, Germany

DOI:

https://doi.org/10.1080/17453674.2021.1873603

Abstract

Background and purpose — Temporary hemiepiphysio- desis for growth modulation in skeletally immature patients is a long-known technique. Recently the use of tension-band devices has become popular. This study compares 2 tensionband implants (eight-Plate and FlexTack) regarding their effects on the growth plate.

Animals and methods — 12 pigs in 2 equally sized groups (A and B) were investigated. The right proximal medial tibia was treated with either eight-Plate or FlexTack. The left tibia of the same pig was treated with the opposite implant. After 9 weeks all implants were removed. Animals in group B were then hosted for another 5 weeks. Histomorphometric analysis of the growth plate was carried out after 9 and 14 weeks, respectively. Radiographs were taken at implantation, removal, and after 14 weeks.

Results — Both tension-band devices achieved a statis- tically significant and clinically relevant growth inhibition, whereas the effect appeared to be more distinct after the use of FlexTack. Implant-related complications or physeal damage was not observed. After implant removal, rebound phenomenon was radiologically observed in all cases. The growth plates treated with eight-Plate showed a paradox reversal of the zonal distributions, with an increase of the proliferative zones at the previously arrested medial aspect of the physis and a decrease laterally.

Interpretation — Both eight-Plate and FlexTack proved to be appropriate devices for growth-guiding treatment. The radiographic evaluation showed a change in angular axes after treatment with each implant, while the correction appeared to be faster with FlexTack. The paradox cartilaginous reaction observed after removal of the eight-Plate might be a histopathological correlate for rebound phenomenon.